Nine Billion Years of Neutral Gas Evolution

Session

Outflow and inflow [chair: Celine Peroux]

4

Jul 30, 2019, 1:20 PM

Eridanus Auditorium (ESO)

Contribution list Timetable

63. Looking for signposts of gas accretion and galactic feedback at the disk-CGM interface

Sanchayeeta Borthakur

7/30/19, 1:20 PM

While gas accretion and feedback are theorized to make significant changes to the state of the circumgalactic medium (CGM) at the disk-CGM interface, the observational evidence to support that is not conclusive. The need of the hour is to measure the properties of the gas in this highly sensitive interface region to connect them to the physics of accretion and outflow. I will discuss the...

52. Extra-planar HI and galactic fountain cycle in nearby late-type galaxies

Antonino Marasco

7/30/19, 1:50 PM

In the last two decades, deep HI observations of nearby late-type galaxies have revealed the presence of extra-planar HI layers extending up to a few kpc above the galaxy midplane and accounting for ~10% of the total HI content. In the few cases studied in detail, these HI layers were found to be characterised by a slow-rotating, globally inflowing kinematics, which is expected by gas in a...

14. Project AMIGA: HI and ionized metals in the circumgalactic medium of the Andromeda Galaxy

J. Christopher Howk (U. Notre Dame)

7/30/19, 2:10 PM

The Andromeda galaxy provides unique opportunities to study the structure of galaxies like our own Milky Way in great detail. I will report on the results from Project AMIGA (Absorption Maps In the Gas of Andromeda), which combines one of the most sensitive surveys to date for circumgalactic HI 21cm emission with searches for metal absorption using HST/COS ultraviolet spectroscopy of ~30...

62. Uncovering the hidden iceberg structure of the gaseous Galactic halo

Vanessa Moss (ASTRON/University of Sydney)

7/30/19, 2:30 PM

How the Milky Way gets its gas and keeps its measured star formation rate going are both long-standing mysteries in Galactic studies, with important implications for the relationship of galaxies to their circumgalactic media throughout the Universe. I will present our discovery of two populations of neutral hydrogen (HI) in the halo of the Milky Way: 1) a narrow line-width dense population...

15. How to identify galaxies which have experienced recent inflow of gas?

Michał Michałowski (Astronomical Observatory Institute, Adam Mickiewicz University)

7/30/19, 3:20 PM

I will present observational evidence that galaxies hosting gamma-ray bursts (GRBs) and some types of supernovae (SN) can be used to study very recent inflow of metal-poor atomic gas from the intergalactic medium. This is supported by their high atomic gas content, irregular velocity fields, potential deficiency in molecular gas, and anomalous metallicity decrements at the position of the most...

57. Cold gas regulating the nuclear activity of Fornax A

Filippo Maccagni (INAF - OAC)

7/30/19, 3:40 PM

Observing neutral hydrogen gas (HI) in well-resolved active galactic nuclei (AGN) is ideal to test how cold gas may fall onto the central super-massive black hole of a galaxy and regulate the nuclear activity. In the centre of several AGN, HI is typically found to be distributed in a circumnuclear disk, but sometimes it is found within in-falling clouds, that is likely fuelling the AGN or in...

56. An HI survey of the Fornax galaxy cluster

Alessandro Loni (Istituto Nazionale di Astrofisica)

7/30/19, 4:00 PM

We present a deep, blind, HI survey of the Fornax galaxy cluster carried out with the Australian Telescope Compact Array (ATCA). The Fornax galaxy cluster is significantly different from the well studied Virgo cluster, as the density of the intra-cluster medium and the velocity dispersion of Fornax are a factor of 2 lower, while the galaxy number is twice as large. These conditions enable the...

45. How can local HI surveys inform the analysis of higher redshift surveys?

Barbara Catinella

7/30/19, 4:20 PM

In this talk, I will present recent results based on xGASS, the extended GALEX Arecibo SDSS Survey, as well as spectral stacking of a large stellar mass-selected sample with HI data from ALFALFA, and discuss implications for future HI surveys. In particular, I will focus on spatially unresolved, local HI surveys, both blind and targeted, and show how these are important not only to define the...